CVE-2026-57029

Junos OS Evolved: QFX Series: When sFlow collector reachability changes evo-pfemand process can crash

MEDIUM
5.3
CVSS Score
Published: July 9, 2026 at 09:12 PM UTC
Updated: October 25, 2026 at 03:10 PM UTC
2 products affected across 2 vendorsJunos OS EvolvedJunos OS Evolved· also runs on 14 platforms

Using Junos OS Evolved by Juniper Networks?

Get instant alerts when new vulnerabilities affect Junos OS Evolved - before attackers find them.

Real-time alertsTrack your software stackFree plan available
Severity
MEDIUM5.3
Exploit prediction
EPSS 0.2%
SSVC
No known exploit

Description

A Missing Synchronization vulnerability in the flow collector handler of Juniper Networks Junos OS Evolved on QFX Series allows an adjacent, unauthenticated attacker to cause a Denial-of-Service (DoS). When the reachability of an sFlow collector changes, the corresponding next-hop entry is updated. If this update occurs simultaneously with the sFlow thread accessing the next-hop data (which is outside the attackers control), it causes the evo-pfemand process to crash, impacting all traffic forwarding until the automatic process restart has completed. This issue affects Junos OS Evolved on QFX Series: * all 23.2 versions,  * 23.4 versions before 23.4R2-S7-EVO, * 24.2 versions before 24.2R2-S5-EVO, * 24.4 versions before 24.4R2-S3-EVO, * 25.2 versions before 25.2R2-EVO.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

juniper-qfx10008 (environment) · juniper-qfx10016 (environment) · juniper-qfx5110 (environment) · juniper-qfx5120 (environment) · juniper-qfx5130 (environment) · juniper-qfx5140 (environment) · juniper-qfx5200 (environment) · juniper-qfx5210 (environment) · juniper-qfx5220 (environment) · juniper-qfx5230-64cd (environment) · juniper-qfx5240 (environment) · juniper-qfx5241 (environment) · juniper-qfx5250 (environment) · juniper-qfx5700 (environment)
v < 23.4R2-S7-EVO24.2 ≤ v < 24.2R2-S5-EVO24.4 ≤ v < 24.4R2-S3-EVO25.2 ≤ v < 25.2R2-EVO24.224.425.2
Affected range stops below 23.4R2-S7-EVO, so it looks safe — our inference, not a vendor statement
Affected range stops below 24.2R2-S5-EVO, so it looks safe — our inference, not a vendor statement
Affected range stops below 24.4R2-S3-EVO, so it looks safe — our inference, not a vendor statement
Affected range stops below 25.2R2-EVO, so it looks safe — our inference, not a vendor statement

Runs on — not affected

The affected product only carries this flaw when running on these platforms. The platforms themselves are not vulnerable.

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

Patch and advisory references

References (1)

Vendor Advisory
Source: cverecord
https://supportportal.juniper.net/JSA110089

SSVC — Action Prioritization

SSVCNo known exploitNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

5.3MEDIUMjuniper
Attack Vector
ADJACENT_NETWORK
Complexity
HIGH
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH
Vector?

Quick Info

StatusANALYZED
CWE
CWE-820

Get alerted

Stop reading CVE feeds looking for your own stack

Track the products you run and VulnTracker tells you when a new CVE affects them — with what is known about fixing it, and nothing about the rest.

Free plan, no card